Lighting unit



L. C. DOANE LIGHTING UNIT Jan. 4, 1927.

Filed Jan. 5 1925 INVENTOR.

A TTORNEYZ.

Patented J an. 4, 1927.

UNITED STATES 1,612,856 PATENT OFFICE.

LEROY C. DOANE, OF MERIDEN, CONNECTICUT, ASSIGNOR TO THE MILLER COMPANY, OF MERIDEN, CONNECTICUT, A CORPORATION OF CONNECTICUT.

LIGHTING UNIT.

Application filed January 3, 1925.- Serial No. 810;

The object of this invention is the manufacture of a lighting unit which while acting in the main as a unit of the indirect type will have the additional advantage of 5 being totally enclosed and evenly luminous to the eye.

The figure is an elevation broken away to disclose a vertical cross section with representative light rays from the source plotted to give a general idea of the general scheme oflight direction and dispersion in the unit.

The main features of my invention consist of a reflector flaring upwardly and encircling the source and having an upper and.

lower opening and an enclosing bowl which completely surrounds both reflector and source.

In the figure l'is the light source, here shown as an electric lamp. the centerbeing chosen for graphic purposes to show the characteristics of the rays of light. 1s the lamp socket or receptacle and 3 1s a holder fitting around the pipe or stem. To the holder. by means of screw 4 is attached a sleeve 5, the bottom of which is provided with a lip 7. Resting on the lip is a flarlng shade 13 of translucent glass which is further held in place by a ring 6 passing around the base of the sleeve. This shade 13 forms part of the totally enclosing globe 12, the remainder of which is composed of a glass enclosure 14 provided with a base 15 which is composed of translucent glass of a denser 5 type than part 13. The lower part 14 of bowl 12, is attached to the upper shade 13 of the bowl by means of a flanged ring 16 and held in place by means of screw 17 passing through to the upper, lip 19 of bowl 1 1. 0 A flaring reflector 11 open top and bottom and encircling the source within the bowl, is held in place by its upper rim, which passes around the upper lip 19 of the bowl, the screw 17 passing through ring 16 and the 5 rim of the reflector to the lip 19 of the lower bowl. The reflector is also held by its lower rim by hooks 10 of arm 20, the upper extremity of these arms being attached to the interior of the bottom of sleeve 5 by means of screws 8. A metal ring 18 passes around the inner edge of the base portion of the bowl for purposes hereinafter set forth.

Reflector 11 is preferably composed of 56 metal which will give a large indirect component to the ceiling. For instance, such rays as s and t will all be acted upon by this reflector and sent upwardly in directions 8' and t. Ray r will not strike the reflector but will pass upwardly to the ceiling or upper surrounding walls through the clearer glass portion 13 of the bowl. In spite of the large indirect component passing upwardly through the upper opening of the reflector 11 such rays as u and 'v passing directly through the lower part 15 of the bowl 12. Owing to the fact that the lower part 15 of bowl 12 is composed of dense glass producing a certain amountof surface reflection on the interior, a portion of the beam whichpasses through the lower opening of reflector 11 will be reflected from the inner surface of 15 in directions u and a and 1?, etc. Such reflected rays as u and u v will strike the reflecting surface of reflector 11 and be again reflected in directions u and u for emission by the lower bowl 14 of envelope 12. It will be readily seen that the entire surface of envelope 12 is rendered luminous by rays which are directly incident from the source or are reflected by the outer surface of the interior reflector. In practice, it may be found necessary to place the reflecting ring 18 around the rim of the lower part of the bowl in order to prevent any unevenness in the visible luminosity of the envelope. This ring having a reflecting outer and inner surface permits rays striking it to be sent upward to'the outer surface of the reflector and also through the lower part 15.

'While other materials may be employed I have foundthat aluminum having a mat finish outside and inside is the material preferable for reflector 11 and for ring 18. The lower bowl 14 can be composed of any white glass of medium density while upper shade 13 is preferably clear. The unit is designed to give a semi-indirect distribution with low intensities on the side and a-- relatively high direct component through the bottom.

I claim: 1. A lighting fixture having a holder, a source of light, an open mouthed reflector open top and bottom around the source of light, and a totally enclosing globe having an upper clear zone transmitting light upwardly direct from the source and from the reflector and a denser lower zone ada ted to transmit directly a portion of the llght 9 rays below the source and to reflect a portion thereof to the outside of the reflector for reflection to and transmission by the denser zone.

2. A lighting fixture having a holder. a source of light, an open mouthed flaring metal reflectoropen top and bottom around the source of light, and a totally enclosing globe having three zones an upper clear zone transmitting light upwardly direct from the source and from the reflector, a denser lower zone adapted to transmit directly .a portion of the light rays below the source and to reflect a portion thereof to the outside of the reflector for reflection to and transmission by the intermediate zone the globe.

3. A lighting fixture having a holder, a source of light, an open mouthed reflector open top and bottom around the source of 20 a reflecting ring adapted to transmit directly 25 a portion of the light rays below the source and to reflect a portion thereof to the outside of the reflector for reflection to and trans-t mission by the denser zone.

Signed at Meriden, in the county, of New Haven and State of Connecticut this 30th day of December, 1924.

LEROY C. DOANE. 

